Category Archives: Optical Transponder

Introduction to WDM Transponders

With the development of wavelength-division multiplexing (WDM) technology, the network traffic volume is increasing and the demand for more network bandwidth is also on the rise. By converting the operating wavelength of the incoming bitstream to an ITU-compliant wavelength, WDM transponder serves as a key component in WDM system. As an important technology in the fiber optical network, WDM is moving beyond transport to become the basis of all-optical networking. And how to optimize WDM network has always been a hot topic. The transponder is a device to optimize the performance of WDM network, which plays an important in the whole system of WDM network. This article will introduce you the information on WDM transponders.

What Is a WDM Transponder?

Also called as an OEO (optical-electrical-optical) transponder, a WDM transponder is an optical-electrical-optical wavelength converter, which has been widely adopted in a variety of networks and applications. The picture below shows us how a bidirectional transponder works. In this picture, the transponder is located between a client device and a DWDM system. And we can see clearly that, from left to right, the transponder receives an optical bitstream operating at one particular wavelength (1310 nm), and then converts the operating wavelength of the incoming bitstream to an ITU-compliant wavelength and transmits its output into a DWDM system. On the receive side (right to left), the process is reversed. The transponder receives an ITU-compliant bit stream and converts the signals back to the wavelength used by the client device.

WDM transponder

The Application of a WDM Transponder

According to its function, the application of a WDM transponders can be classified into the following types.

  • Wavelength Conversion. It is known to us that when a CWDM Mux/Demux or DWDM Mux/Demux is added into a WDM network, there is a requirement to convert optical wavelengths like 850nm, 1310nm and 1550nm to CWDM or DWDM wavelengths. Then the OEO transponder comes to assist. The OEO transponder receives, amplifies and re-transmits the signal on a different wavelength without changing the signal content.
  • Fiber Mode Conversion. Multimode fiber optic cables (MMF) are often used in short distance transmission, while single-mode fiber optic cables (SMF) are applied in long optical transmission. Therefore, in some network deployment, considering the transmission distances, MMF to SMF or SMF to MMF conversions are needed. WDM transponders can convert both multimode fiber to single-mode fiber and dual fiber to single fiber.
  • Signal Repeating. In long haul fiber optic transmission, WDM transponder also can work as repeaters to extend network distance by converting wavelengths (1310nm to 1550nm) and amplifying optical power. The OEO converters convert the weak optical signals from the fiber into electrical signals, and regenerate or amplify, then recover them into strong optical signals for continuous transmission.
WDM Transponder and FMT Solution

At FS, OEO transponders are made into small plug-in cards to be used on the FMT platform. FMT platform makes devices like EDFA, OEO, DCM, OLP and VOA into plug-in cards and provides standard rack units as well as free software to achieve better management and monitoring. In addition, FMT series products like OEO, DCM and OLP also have higher performance than that of old ones. FMT series OEO transponder can convert optical signals into DWDM wavelengths, reducing the fault risk caused by high power consumption of DWDM fiber optic transceiver. Since the OEO transponder is made into small plug-in card in the FMT platform, it only occupies one slot in the special designed chassis when installed, thus saving a lot of space. In addition, all these FMT plug-in cards, including OEO, in a rack unit share the same power source and support hot plug & play operation. And they can be inserted or removed flexibly in the racks for DWDM networking.

FMT

Conclusion

Since the OEO transponder plays an important role in WDM network, such as receiving, amplifying and re-transmitting the signal on a different wavelength, adding an OEO transponder into the WDM network is very essential. The OEO transponders in our FMT series are made into small plug-in cards with high quality to ensure good transmission performance. For more information on our FMT system, please visit www.fs.com.

OEO 3R Converter Instruction

Optical signals are transmitted on specific wavelengths like 850nm, 1310nm, 1550nm and CWDM wavelengths and DWDM wavelengths. In some cases, it occurs that you need to converter a wavelength of optical signals into another wavelength for transmission. A useful component OEO 3R converter is suggested to be used. The OEO converter is also known as transponder OEO. This component uses the Optical-Electrical-Optical principle to offer the conversion between different wavelengths of optical signals. “3R” means re-timing, re-shaping, and re-amplifying.

OEO 3R

OEO 3R Converter for Wavelength Conversion

OEO 3R converter can fit various applications and can be installed in the network flexibly. It is a very popular component in DWDM and CWDM networks. In many situations, we are using fiber optic transceiver that working on 850nm, 1310nm and 1550nm for optical signal transmission. However, if you want to add optical signals of these wavelengths into a CWDM or DWDM network, you should firstly convert the wavelengths into CWDM or DWDM wavelengths. With OEO converter, this could be easy. The following picture shows a case which uses OEO converter in a CWDM network for wavelengths conversion.

OEO WDM

In this case, a 10G SFP+ to SFP+ OEO with two SFP+ ports, is being used for wavelength conversion between 1310nm and CWDM wavelength 1610nm. A 10G-LR SFP+ module working on 1310nm is used in a 10G switch on site A. To add the optical signal of this port in to the existing CWDM network, this module is being connected to another 10G LR SFP+ module which is being inserted in the SFP+ Port 1 of the OEO converter. A CWDM 1610nm SFP+ module, connected to the CWDM MUX/DEMUX on site B, is being used in the other port of this OEO converter. The OEO converter the 1310nm signal into 1610nm CWDM signal. The optical signal from site A is being added into the CWDM network via the CWDM MUX/DEMUX on site B.

OEO 3R Converter for Fiber Mode Conversion and Fiber Repeating

The using of OEO converter for wavelength conversion is simple. As above mentioned, the OEO 3R converter has the function of re-timing, re-shaping, and re-amplifying, the OEO 3R converter can also be used as fiber mode converter and fiber repeater converters. The following picture shows another case with OEO 3R converter working as fiber repeater and providing conversion between single-mode and multimode.

OEO 3R

In this case, three SFP+ to SFP+ OEO converters are deployed between Site A and Site B for long distance dual-way optical transmission. The optical signal from Site A is firstly converted from multi-mode fiber into single-mode fiber for 90km transmission by one OEO converter. Then, a second OEO converter is used as a repeater to “3R” the optical signals. After that, the single-mode signal will travel another 75km. Before the signal reaches the switch in Site B, another OEO converter converts the single-mode signal into multimode signal.

OEO Converter Options

OEO converters provide flexible solution for optical transmission network. Except the above mentioned 10G SFP+ to SFP+ OEO converter, there are many other OEO converters with different port types, port counts and designs. The following table listed several OEO converters for your reference.

 SFP+ to SFP+ OEO  XFP OEO
SFP+ to SFP+ OEO Converter XFP to XFP OEO Converter
 QSFP+ OEO  8 SFP+ OEO
QSFP+ to QSFP+ OEO Converter 8 Ports SFP+ 10G OEO Converter

Overview of Extreme Networks SFP Modules Interface Types

Introduction
Extreme Networks is a networking company which designs, builds, and installs Ethernet computer network products for enterprise and carrier grade (metro) networks using the speed and scale of 10 Gigabit Ethernet, 40 Gigabit Ethernet and 100 Gigabit Ethernet. Extreme Networks switches support both optical and copper SFP (small form factor pluggable) modules. The types of switches and the I/O modules determine the compatible type of SFP module. This paper will introduce the Extreme Network SFP modules and the matching switches. What’s more, an alternative solution is offered here which can give you a low cost option.

Extreme SFP Transceiver

Types of Extreme Networks SFP Interfaces
Extreme Networks switches support the following types of optical SFP interfaces:

SX SFP module
The SX SFP module provides a 1000BASE-T optical connection using LC connectors and multimode fiber cable up to 300 meters long. The SX SFP module conforms to the 1000BASE-SX standard.

  • Matching Switches: BlackDiamond 10808\BlackDiamond 8800 series\BlackDiamond 12800 series\Summit X150 series\Summit X250e series\Summit X450 series\Summit X450a series\Summit X450e series

LX SFP module
The LX SFP module provides a 1000BASE-T optical connection using LC connectors and single-mode fiber (SMF) cable up to 10 km long. The LX SFP module conforms to the 1000BASE-LX standard.

  • Matching Switches: BlackDiamond 10808\BlackDiamond 8800 series\BlackDiamond 12800 series\Summit X150 series\Summit X250e series\Summit X450 series\Summit X450a series\Summit X450e series

ZX SFP module
The ZX SFP module is a long-haul SFP that provides a 1000BASE-T optical connection using LC connectors and SMF cable up to 80 km long.

  • Matching Switches: BlackDiamond 10808\BlackDiamond 8800 series\BlackDiamond 12800 series\Summit X150 series\Summit X250e series\Summit X450 series\Summit X450a series\Summit X450e series

1000BASE-BX bidirectional SFP modules
The 1000BASE-BX SFP modules include the 1000BASE-BX-U SFP module and the 1000BASE-BX-D SFP module. These two SFP modules are used together to permit a bidirectional Gigabit Ethernet connection using a single strand of SMF cable and LC connectors. The 1000BASE-BX-D SFP operates at wavelengths of 1490 nm TX/1310 nm RX, and the 1000BASE-BX-U SFP operates at wavelengths of 1310 nm TX/1490 nm RX. The 1000BASE-BX-U SFP module is always connected to the 1000BASE-BX-D SFP module. The maximum transmission distance for this connection is 10 km. The 1000BASE-BX SFP modules conform to the IEEE 802.3ah 1000BASE-BX10 standard.

  • Matching Switches: BlackDiamond 10808\BlackDiamond 8800 series\BlackDiamond 12800 series\Summit X150 series\Summit X250e series\Summit X450 series\Summit X450a series\Summit X450e series

100FX SFP module for Gigabit Ethernet ports
The 100FX SFP module for Gigabit Ethernet (GE) ports (Model # 10063) provides optical links up to 2km long using multimode fiber cable. The 100FX SFP for GE ports conforms to the 100FX-MMF standard.

  • Matching Switches: BlackDiamond 8800 series(G24x I/O module, MSM-G8x module, G48Xa I/O module)/ Summit X250e series (Summit X250e-24t, X250e-24p, X250-48t, X250e-48t: combination ports only, Summit X250e-24x: all ports)/Summit X450a-24x switch (ports 5 through 24; not supported on combination ports)/Summit X450a series ( not supported on combination ports)

Dual-speed 100FX/1000LX SFP module
The dual-speed 100FX/1000LX SFP module operates at either 100 Mbps or 1000 Mbps over SMF links up to 10 km long. Operating at 100 Mbps, the dual-speed SFP conforms to the 100BASE-LX standard. Operating at 1000 Mbps, the dual-speed SFP conforms to the 1000BASE-LX standard.

  • Matching Switches: BlackDiamond 8800 series/BlackDiamond 12800 series/Summit X150 series/Summit X250e-24t, X250e-24p, X250e-48t, X250e-48p switches: combination ports only/Summit X450-24x switch: ports 5 through 24 (not supported on combination ports)/Summit X450a-24x, X450a-24xDC switches: ports 1 through 20 (not supported on combination ports)

LX100 SFP module
The LX100 SFP module provides a 1-gigabit optical link up to 100 km long using LC connectors and SMF cable.

  • Matching Switches: BlackDiamond 10808\BlackDiamond 8800 series\BlackDiamond 12800 series\Summit X150 series\Summit X250e series\Summit X450 series\Summit X450a series\Summit X450e series

100BASE-LX10 SFP module
The 100BASE-LX10 SFP module provides a 100-Mbps optical connection using LC connectors and SMF cable. The maximum transmission distance for this connection is 10 km.

  • Matching Switches: The LX10 SFP module is supported in the Summit X250e-24x switch in all ports.

100BASE-BX SFP modules
The 100BASE-BX SFP modules include the 100BASE-BX-U SFP module and the 100BASE-BX-D SFP module. These two SFP module are used together in a Summit family switch to permit a bidirectional 100-Mbps Ethernet connection using a single strand of SMF cable and LC connectors. The 100BASE BX-U SFP module is always connected to the 100BASE-BX-D SFP module. The 100BASE-BX-D SFP operates at wavelengths of 1550-nm TX/1310-nm RX wavelength), and the 1000BASE-BX-U SFP operates at wavelengths of 1310 nm TX/1550 nm RX. The maximum transmission distance for this connection is 10 km. The 100BASE-BX SFP modules conform to the IEEE 802.3ae standard.

  • Matching Switches: The 100BASE-BX SFP modules are supported the Summit X250e-24x switch in all ports

100FX SFP module for 100-Mbps Ethernet (fast Ethernet) ports
The 100FX SFP module for fast Ethernet (FE) ports (Model # 10067) provides a 100-Mbps optical link using LC connectors and 1310-nm multimode fiber (MMF) cable. The maximum transmission distance for this connection is 2 km.

  • Matching Switches: The 100FX SFP module for FE ports is supported in the Summit X250e-24x switch in all ports

10/100/1000BASE-T Copper SFP Module
The Extreme Networks 10/100/1000BASE-T copper SFP module is compatible with the Gigabit Ethernet standard and 1000 Base-T standard as specified in the IEEE 802.3:2002 standard. This SFP module provides a 100-Mbps connection using Category 5 cable.

  • Matching Switches: BlackDiamond 8800 series\Summit X450 series\Summit X450a series

Extreme Network SFP Module Alternative Solution
Extreme compatible SFP transceiver support Ethernet, Sonnet/SDH and Fiber Channel applications across all Extreme switching and routing platforms. Fiberstore offers cost-effective standards-based Extreme Compatible SFP Transceivers. As a 3rd party OEM manufacturer, our Extreme SFP is delivered to worldwide from our factory directly. All of our Extreme SFP optical transceivers are tested in-house prior to shipment to guarantee that they will arrive in perfect physical and working condition. The best part of our Extreme Network compatible transceiver modules is that you won’t have to sacrifice any quality or reliability with all of the savings you receive. In contrast, you get everything you’ve come to expect from our Cisco transceivers at up to 90% off list price. Get more information about fiber optic transceiver solution (other brands such as Cisco, Finisar, HP, Dell etc. are available) can visit our official website.

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